Abstract: This work reports the use of response surface methodology to optimize conditions for the extraction of arachin and conarachin from defatted soybean meal. Defatted soybean meal was suspended in 0.03 mol/L Tris-HCl buffer at a constant temperature and stirred for 1 h. As a result, arachin and conarachin were extracted into the supernatant. Temperature, pH and solvent/solid ratio were tested for their effects on the solubility of arachin and conarachin. The best solubility of arachin and conarachin was observed when the extraction conditions were 62.93 ℃, pH 9.04 and 15.11:1 (mL/g). In addition, the experimental NSI values of arachin and conarachin were 54.82% and 74.1%, respectively, which were close to the predictive values. Accordingly, response surface methodology can be a reasonable and feasible approach to optimizing conditions for the extraction of peanut proteins.

Key words: arachin, conarachin, solubility, response surface methodology